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Gravity guru will shed its hold, briefly

This afternoon, a nurse will carry Stephen Hawking onto a cargo jet at Kennedy Space Center so he can fly 6 miles up in a modified Boeing 727 and experience a few precious minutes of weightlessness.

Hawking, 65, is a world-renowned theoretical physicist from Cambridge, England, whose work and writing on the relationship between dead stars and gravity have increased understanding of the cosmos.

The one thing Hawking doesn't know about gravity is what it feels like to be free of it.

Hawking's brain soars in a body so physically disabled by an incurable muscular disease that he cannot speak, eat or breathe on his own. For some time, his mind has been focused on space in less abstract ways than he is accustomed.

He has said he is taking the weightless flight because he "has studied gravity and black holes" his entire life and wants to "experience firsthand weightlessness." The trip, he said, is a step toward going into space in 2009.

When the Fort Lauderdale company Zero Gravity heard about his goal, the CEO offered Hawking a free ride. Zero Gravity bills itself as a "privately held space entertainment and tourism company." Besides being a location for commercials 7 Up and movie scenes (Apollo 13), the company offers weightless flights for holiday parties and sales meetings.

This time, however, the flight has a more serious purpose, which is why Mike Bougher will be surfing the Internet to get news of it.

Bougher, 42, of Benicia, Calif., a former designer of remote monitoring systems, has the same disease - amyotrophic lateral sclerosis - as Hawking. And like Hawking, he chose life on a ventilator with a feeding tube over death within two to five years, which often occurs when ALS patients don't go on life support.

"The fact that Hawking continued to live a productive life, contributing to civilization in a big way after being diagnosed with a disease that knocks most in the dirt got me contemplating possibilities for my own life," said Bougher in an e-mail. It was Hawking's "passion for life," said Bougher, that helped convince him to go on life support.

Stephen Hawking was diagnosed with ALS in 1962, when he was 20. Bougher was diagnosed in 1996 in his early 30s. Like Hawking, Bougher communicates with a computer that responds to slight movements of his head.

It is Hawking's "refusal to be disabled in spirit" that Bougher will celebrate this afternoon when Hawking, wearing a navy blue NASA flight suit, is hoisted out of his motorized wheelchair and strapped into an airplane seat for a roller coaster ride at 32,000 feet. For the weightless portion of the flight Hawking will be moved to a 70-foot-long padded area called the "floating zone."

With Hawking will be three doctors and two nurses he has brought from England. They will check his vital signs after every maneuver. To achieve the weightless sensation, the plane will perform 15 or more steep ascents and descents.

At the top of each climb the passengers experience about 25 seconds of zero gravity. At the bottom of each descent, the passengers feel as if their body weight is almost double. The medical staff will check the effects of this pressure on his circulatory system.

"As my mother used to say when I was a kid, it's not the fall that hurts but the stop at the end," said Randall Bone, a California developer who will fly with Hawking, his medical entourage and more than a dozen other passengers.

Several, like Bone, have paid more than the usual $3,750 - charged by the flight company - to shed gravity with the scientist who has been writing on the subject for decades. Bone contributed the extra money to ALS research. He wouldn't specify the amount, except to say it's "a lot more."

Bougher worries weightlessness will be a problem for Hawking: "He will have no way to control his movement, and his life line will be connected to his throat. It will be important to keep his body and the ventilator in close proximity."

Before boarding, most passengers will be taking an extra-strong version of Dramamine to prevent vomiting as the plane bucks. (It is laced with caffeine to keep them awake.) Part of Hawking's remedy will be to skip his feeding-tube lunch.

Virgin Galactic sales agent Ryan Hilton, who is selling the 2009 space trips at $200,000 a seat, said he has done the weightless flight in preparation for the space orbit: "You feel yourself lighten and you rise. I'm 6'4" and 230 pounds, and I was doing back flips," he said.

Hawking won't be doing back flips, but he will rise up and float - a first for a quadriplegic person, according to Zero Gravity.

Bougher says he will be following the flight to be reminded of the "endless possibilities" of life: "How you can lose the use of your body, but in return, your mind and spirit can be set free."